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<title>Operands (GNU Compiler Collection (GCC) Internals)</title>

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Next: <a href="Manipulating-GIMPLE-statements.html" accesskey="n" rel="next">Manipulating GIMPLE statements</a>, Previous: <a href="Temporaries.html" accesskey="p" rel="prev">Temporaries</a>, Up: <a href="GIMPLE.html" accesskey="u" rel="up">GIMPLE</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html" title="Index" rel="index">Index</a>]</p>
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<h3 class="section" id="Operands-1"><span>12.6 Operands<a class="copiable-link" href="#Operands-1"> &para;</a></span></h3>
<a class="index-entry-id" id="index-Operands"></a>

<p>In general, expressions in GIMPLE consist of an operation and the
appropriate number of simple operands; these operands must either be a
GIMPLE rvalue (<code class="code">is_gimple_val</code>), i.e. a constant or a register
variable.  More complex operands are factored out into temporaries, so
that
</p><div class="example smallexample">
<pre class="example-preformatted">a = b + c + d
</pre></div>
<p>becomes
</p><div class="example smallexample">
<pre class="example-preformatted">T1 = b + c;
a = T1 + d;
</pre></div>

<p>The same rule holds for arguments to a <code class="code">GIMPLE_CALL</code>.
</p>
<p>The target of an assignment is usually a variable, but can also be a
<code class="code">MEM_REF</code> or a compound lvalue as described below.
</p>

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